基于GRF-3100射频系统的混频器的设计与制作

电子通信论文编号:TX184  论文字数:8375,页数:23

目　　录
第一章  引言………………………………………………………………………1
1.1 射频系统概述……………………………………………………………1
1.2混频器基本原理………………………………………………………2
1.3混频器分类……………………………………………………………3
第二章 混频电路硬件设计……………………………………………………4
2.1主要性能指标…………………………………………………………4
2.2接收机混频器设计……………………………………………………7
2.2.1电路工作原理………………………………………………7
2.2.2 Protel电路设计…………………………………………8
2.3发射机混频器设计…………………………………………………11
2.3.1电路工作原理………………………………………………11
2.3.2 Protel电路设计…………………………………………11
第三章 实际电路制作与测试………………………………………………13
3.1 PCB板选材……………………………………………………………13
3.2 电路焊接………………………………………………………………13
3.3 性能测试………………………………………………………………14
3.3.1测试仪器简介………………………………………………14
3.3.2 测试项目………………………………………………………14
结束语…………………………………………………………………17
主要参考文献………………………………………………………………18
致谢……………………………………………………………………………19

摘    要
射频电路实验系统GRF-3100，工作频率为800MHz,分为射频发射和射频接收两部分。其中混频器是实现频率变换的器件，是射频系统中的一个关键部分。每个无线通信系统都要用到一个以上的混频器，其性能将直接影响整个系统的性能。混频器组成模型是相乘器和带通滤波器，其主要技术指标有混频增益、隔离度、混附信号、1dB压缩电平、互调失真，噪声指数等。本文从整个射频系统出发，参照射频电路实验系统GRF-3100技术手册，对系统中用到的双栅极混频器和晶体管混频器的设计及其特性进行了独立的分析和研究，并且介绍了电路设计的整个流程：分析电路原理，电路原理图及PCB图设计，实际电路焊接，调试及性能测试。此外，本文对相关的Protel DXP软件，表面安装技术(SMT)及频谱分析仪操作也有所介绍。

关键词：射频系统；双栅极混频；晶体管混频

Based On RF System GRF-3100 Mixer Design

Abstract
RF circuit GRF-3100 experimental system, the operating frequency of 800MHz，is divided into RF transmitter and RF receiver. Mixer which is the frequency conversion component is a key part of RF system. Each wireless communication systems always use over a mixer. Its performance will directly impact the performance of the whole system. Mixers model is composed of  Multiplier and band-pass filter, and the main technical indicators of mixers are Conversion Gain, Isolation, Spurious Signal, 1dB Compression Level ，Intermodiation Distortion, Noise Figure and so on. The design of Dual Gate Mixer and transistor mixer is investigated and their performances are analyzed, which according to RF circuit experimental system GRF-3100 technical manual. In addition, this paper describes the entire process of the circuit design: circuit analysis, circuit diagram and PCB layout design, the actual circuit welding, debugging and performance testing. Finally, the paper also introduces the relative knowledge of the Protel DXP software, Surface Mounting Technology (SMT) and the spectrum analyzer.

Keywords: radio frequency system; dual gate mixer；transistors mixers